The present invention relates to the generation of fonts, and more particularly, to the use of composite fonts to minimizing the font storage area for an apparatus using a plurality of different fonts.
With the increasing number of electronic devices that are usable with a wide variety of applications and within a number of markets and countries wherein different languages are used, the amount of storage for numerous types of fonts has become increasingly problematic. Fonts may comprise one of a number of different types. Vector based and synthesized fonts (for example TrueType) may be used for larger characters and do not require a significant amount of storage space for containing the fonts. However, vector based and synthesized fonts do not work very well for smaller characters having a small number of pixels. Instead, bitmap fonts are used for smaller characters wherein each character is handmade at the pixel level. Unfortunately, bitmap fonts require a large amount of storage area, especially in the case of Chinese and Japanese character sets, and even a greater amount of storage area when a variety of styles are required for the different characters such as various point sizes, bolded versus non-bolded characters and italicized versus non-italicized characters.
The main problem arising from the use of bitmap fonts comes from the storage requirements which are necessary to store information on a large number of fonts. For example, several hundred kilobytes may be required for just one font. Thus, if each character requires five different point sizes, three different types of bolding and three different types of italics for each character, the storage space necessary for the font can easily take up five to ten megabytes. Since many types of portable electronic equipment may only contain a few megabytes (for example, four megabytes) of flash memory for storage, this type of storage requirement is unacceptable. The only presently known solution is to limit the number of styles in order to save resources, however, this sacrifices the look and appearance of the characters upon a display. Thus, present solutions to this problem must either limit the look of characters provided by display or increase the application complexity in order to make the best use of the available fonts.
The present invention overcomes the foregoing and other problems with a method and apparatus for composite font generation. In a first embodiment, a font system includes a plurality of font files, each of which stores bitmaps associated with a range of characters. The plurality of font files only contains a single version of each bitmap for a character. Associated with the plurality of font files are a plurality of composite font files which contain a number of pointers pointing to ones of the plurality of font files. Each font file may have one or more pointers pointing at the font file.
In a further embodiment, the font system again includes the plurality of font files each of which stores bitmaps associated with a particular range of characters. The plurality of font files again only contain a single version of a bitmap for a character. A rules set enables the generation of a selected font responsive to a print request. The rules, in response to the print request, select a desired font file based upon the established rules in order to print the requested character.